One of the most devastating and costly consequences of excessive alcohol use is mortality. The mortality effects of alcohol appear to be most severe among alcohol-involved offenders, but to our knowledge there are no studies based on US samples. Research to identify community-level strategies that effectively reduce alcohol-related harms has produced mixed results and very little evidence on mortality. The varying degrees of success may be explained, in part, by the extent to which these interventions target those drinkers most likely to impose harms. The study addresses two important gaps in the literature. First, we provide the first rigorous documentation of excess mortality among alcohol-involved offenders in the US. Second, we evaluate whether South Dakota's 24/7 Sobriety Program (hereafter 24/7), which has been effective in reducing heavy drinking and criminal justice consequences, has implications for mortality. Alcohol use is particularly problematic among criminal justice populations. In traditional community supervision models, sanctions for violations-if applied at all-often occur only after fairly serious offenses and may not be imposed until weeks or months after the precipitating offense. But, a growing body of evidence suggests that punishment certainty and celerity create a stronger deterrent to illegal activity than severity, especially among alcohol-abusing populations. South Dakota's 24/7 applied the concept of frequent testing in combination with swift and certain (but mild) sanctions for alcohol violations to alcohol-involved offenders living in the community. RAND's NIAAA-funded evaluation, published in the American Journal of Public Health, provides evidence that the program reduced heavy drinking and reduced the prevalence of arrests for repeat drunk driving by 12%, arrests for domestic violence by 9%, and traffic crashes among young males by 4% at the county-level. Given the program's success in reducing heavy drinking episodes and criminal justice consequences, it is natural to consider whether its benefits extend to public health outcomes - among which mortality is the most costly. Exploiting a unique individual-level dataset linking criminal records, 24/7 participation and mortality records for a cohort of offenders, we will first document mortality among this high- risk population and then consider whether/how 24/7 influenced their mortality. While 24/7 is being adopted or considered in several smaller states and jurisdictions, it has not yet been widely accepted by larger jurisdictions despite its recent addition to the list of impaired driving countermeasures eligible or U.S. Department of Transportation funds (MAP-21; P.L. 112-141). Recent comments from the Vice President of Public Policy for Mothers Against Drunk Driving and debates among criminal justice scholars demonstrate a resistance to the program's approach despite emerging evidence of reductions in heavy drinking and criminal justice consequences. Thus, findings from this study will provide further evidence to inform the debate on whether 24/7 is an effective means of safeguarding public safety and health.